Found here.

B. Scientific acoustical evidence establishes a high probability that two gunmen fired at President John F. Kennedy. Other scientific evidence does not preclude the possibility of two gunmen firing at the President. Scientific evidence negates some specific conspiracy allegations.

C. The committee believes, on the basis of the evidence available to it, that President John F. Kennedy was probably assassinated as a result of a conspiracy. The committee is unable to identify the other gunman or the extent of the conspiracy.

1. The committee believes, on the basis of the evidence available to it, that the Soviet Government was not involved in the assassination of President Kennedy.
2. The committee believes, on the basis of the evidence available to it, that the Cuban Government was not involved in the assassination of President Kennedy.
3. The committee believes, on the basis of the evidence available to it, that anti-Castro Cuban groups, as groups, were not involved in the assassination of President Kennedy, but that the available evidence does not preclude the possibility that individual members may have been involved.
4. The committee believes, on the basis of the evidence available to it, that the national syndicate of organized crime, as a group, was not involved in the assassination of President Kennedy, but that the available evidence does not preclude the possibility that individual members may have been involved.
5. The Secret Service, Federal Bureau of Investigation and Central Intelligence Agency were not involved in the assassination of President Kennedy.

Who it actually was who conspired, they never managed to find out . . .